COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 106 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Lycoming Piston Engines
AD/LYC/91 Crankshaft Removal/Inspection 10/92 DM
Applicability: All Textron Lycoming piston engines that have been overhauled by or had the crankcase disassembled for major work by Arnhem Aircraft Engineering Pty Ltd under Certificate of Approval No. 4049 during the period 1 January 1990 to 6 August 1992.
Requirement: 1. Remove the crankshaft assembly and dimensionally check the diameters of all bearing journals.
2. Crankshafts with any bearing journal diameter less than the STANDARD dimension listed in the relevant Textron Lycoming Engine Overhaul Manual are to be quarantined and the CAA local Airworthiness District Office notified.
3. Crankshafts with diameters for all bearing journals at the STANDARD dimension listed in the relevant Textron Lycoming Engine Overhaul Manual may be refitted to an engine.
Compliance: For installed engines - Prior to the 31 August 1992.
For uninstalled engines - Before installation into aircraft.
Background: Four crankshaft assemblies repaired by the grinding of bearing journals on behalf of Arnhem Aircraft Engineering Pty Ltd have been found with grinding cracks, two of which failed in flight. Arnhem Aircraft Engineering Pty Ltd has been unable to satisfy the CAA (Australia) as to the location or number of crankshafts repaired by grinding on its behalf.
Overview
The Civil Aviation Regulations 1998 (Civil Aviation Regulations) were enacted to ensure the safety of civil aviation in Australia and to regulate civil aviation activities. Part 39, particularly the schedule of Airworthiness Directives, provides specific safety requirements for aircraft components, including engine maintenance and inspection. One such directive, AD/LYC/91, addresses crankshaft issues identified in Textron Lycoming piston engines overhauled by Arnhem Aircraft Engineering Pty Ltd. This directive was introduced to address a problem identified with crankshafts repaired by grinding, which had led to failures in flight. The objective of this directive is to ensure that any affected crankshafts are inspected and, if necessary, replaced to maintain the safety standards of civil aviation in Australia. This legislative instrument was enacted by the Commonwealth of Australia and is administered by the Civil Aviation Safety Authority.
Scope and Application
The Civil Aviation Regulations 1998, specifically PART 39 - 106, mandates the Civil Aviation Safety Authority (CASA) Schedule of Airworthiness Directives, including AD/LYC/91, which pertains to Textron Lycoming piston engines. This directive applies to all engines that have undergone overhaul by or had their crankcase disassembled for major work by Arnhem Aircraft Engineering Pty Ltd, under Certificate of Approval No. 4049, during the period from 1 January 1990 to 6 August 1992. The directive requires the removal of the crankshaft assembly and a dimensional check of all bearing journals to ensure compliance with the standards listed in the Textron Lycoming Engine Overhaul Manual. Crankshafts failing to meet the standard dimensions must be quarantined, and the CASA local Airworthiness District Office must be notified. Engines requiring compliance must have the inspection conducted prior to 31 August 1992 if installed, or before installation into aircraft if uninstalled. This directive addresses safety concerns arising from crankshafts repaired by grinding bearing journals, which had instances of cracking and failure in flight.
Key Provisions
The main sections of this legislation (Civil Aviation Regulations 1998, PART 39 - 106) outline the specific requirements for the crankshaft removal and inspection of Textron Lycoming piston engines overhauled by Arnhem Aircraft Engineering Pty Ltd between 1 January 1990 and 6 August 1992. Specifically, section 10/92 DM mandates the removal of the crankshaft assembly and dimensional checks of all bearing journals (section 1). This directive is crucial to ensuring that any crankshafts with bearing journals that are not up to the specified standard dimensions are identified and handled appropriately (section 2). Crankshafts that meet the standard dimensions can be refitted to an engine (section 3). The compliance timeframes are stringent: installed engines must undergo this process before 31 August 1992, while uninstalled engines must be inspected prior to their installation into an aircraft (section Compliance).
The obligations imposed by this Act on the parties involved are clear and specific. Owners and operators of Textron Lycoming piston engines that have been serviced by Arnhem Aircraft Engineering Pty Ltd within the specified time frame must ensure that the crankshaft assemblies are removed and inspected as per the requirements outlined in the directive. This includes dimensionally checking all bearing journals and reporting any crankshafts that do not meet the standard dimensions to the CAA local Airworthiness District Office (section 2). This obligation is critical to maintaining the safety and airworthiness of aircraft utilising these engines.
Failure to comply with the requirements of this directive can lead to significant consequences. While the specific penalties are not detailed in the legislation, the potential outcomes of non-compliance could include enforcement actions by the Civil Aviation Safety Authority, which could range from fines to more severe sanctions if the non-compliance results in safety incidents or accidents. The seriousness of the issue, given that two crankshafts with grinding cracks failed in flight, underscores the importance of strict adherence to the directive to avoid any civil or criminal liabilities that may arise from non-compliance.